Fire extinguisher valves



Nov. 21, 1961 P. M. CARTER ET AL FIRE. EXTINGUISHER VALVES 4Sheets-Sheet 2 Filed D60. 30, 1955 Nov. 21, 1961 P. M. CARTER ET AL FIREEXTINGUISHER VALVES 4 Sheets-Sheet 3 Filed Dec. 30, 1955 m R 4 mm m w mM f D P. M. CARTER ET AL FIRE EXTINGUISHER VALVES Nov. 21, 1961 4Sheets-Sheet 4 Filed Dec. 50, 1955 IN VEN TORS Pym; /P A4. U Y DAN/ELNIZPDOZ/I I II w H I Patented Nov. 21, 1961 3,009,681 FIRE EXTINGUISHERVALVES Philip M. Carter, Ossining, N.Y., and Daniel Nardoza, Keyport,N.J., assignors, by mesne assignments, to The Casco ProductsCorporation, Bridgeport, Conn., a corporation of Connecticut Filed Dec.30, 1955, Ser. No. 556,719 3 Claims. (Cl. 251-332) This inventionrelates to valves and more specifically to an improved valve andcooperating seat assembly that is particularly useful as the valvingmechanism in the discharge head of pressure type fire extinguishers aswell as for other purposes.

In the pressure type fire extinguishers, it is important that thedischarge valve afford a completely dependable closure means to preventthe loss of pressure throughout long periods of time and in additionprovide an easily operable mechanism so that the fire extinguishingmedium can be quickly discharged in time of need. It is also importantthat the valve reclose with full efficiency after each intermittentpartial discharge whether the spacing is at small or great intervals.The attainment of these objectives has not been met satisfactorily bydevices heretofore proposed, notwithstanding their complication andexpense. Where the extinguishing medium has been dry chemical or powder,the prior valves have been signally defective in preventing leakageafter a partial discharge. Moreover, prior known valves, particularlyfor fire extinguisher use, have been both expensive and difficult tomaintain and repair.

Accordingly, an object of the invention is to provide a valve and seatassembly which maintains a tight leakproof joint though undersubstantial pressure for a prolonged period of time.

Another object is to provide such a valve and seat assembly whichrecloses effectively, after partial discharge, regardless of the mediumdischarged.

Another object is to provide such a valve and seat assembly whichrecloses effectively even though the medium discharged be dry.

Another object of the invention resides in the provision of an improvedvalve and seat assembly that functions to wipe the valve seat clean inthe closing operation.

Still another object is to provide a valve and seat assembly wherein thevalve can be seated effectively regardless of the type of pressureemployed.

Still another object is to provide such a valve and seat assembly whichreacts in response to the pressure of the fluid being retained toprovide a complete and permanent seal and prevent loss of pressure.

A further object of the invention resides in the provision of animproved valve and seat assembly that not only insures a good seal butalso enables the valve to be opened quickly to a position of full orpartial flow.

A further object of the invention is to provide a valve which will beself adjusting and can be repaired and re assembled without anyparticular skill.

A still further object of the invention is to provide an improved valveparticularly useful for powder type fire extinguishers that is designedand constructed to provide for the smooth flow of the fire extinguishingmedium past the valve when it is open and to function effectively towipe the valve seat clean as the valve closes to thereby effect a moreperfect seal.

A further general object of the invention is to provide an improvedvalve and seat assembly for pressure type fire extinguishers and otherpurposes.

The above and other objects and advantages of the invention will becomemore apparent from the following description and accompanying drawingsforming part of this application.

In the drawings:

FIG. 1 is a side elevational view of a fire extinguisher having adischarge head incorporating a valve and seat assembly in accordancewith the invention;

FIG. 2 is a top plan view of the discharge head of FIG. 1;

FIG. 3 is a section taken on line 33 of FIG. 2 showing the valve carriedby the head in closed position;

FIG. 4 is a view similar to FIG. 3 but showing the valve in the openposition;

FIG. 5 is an exploded perspective view of the valve member per se;

FIGS. 6, 7 and 8 are enlarged cross sectional views of the valve andseat assembly in accordance with the invention showing the valve indifferent positions of its stroke.

Referring now to the details of the drawings and at the outset to FIGS.1 to 4 thereof, the discharge head of the fire extinguisher is generallydenoted by the numeral 10 and is arranged for suitable attachment to atank 12 in which the fire extinguishing medium is retained underpressure. In the case of an extinguisher utilizing a powder, employingpressures as low as to p.s.i., welded bottles of the type illustratedare generally approved. When powder, such as sodium bicarbonate, isemployed about three-fourths of the tank is usually filled with thepowder and after the head 10 is secured in place on the tank, the latteris charged with air, nitrogen or other suitable inert gas to a pressureof about 190 pounds. Since powder normally tends to settle to the bottomof the tank, a tube 1 3 is secured to the head 10 and extends to withinclose proximity to the tank bottom. The internal diameter of this tubegoverns the maximum rate at which powder can be discharged from theoutlet 14.

The tube 13 can be interchanged with others of different internaldiameter to accommodate different tank sizes and rates of discharge. Forthis purpose the tube 13 is provided with an enlarged screw threadednipple 15 at one end thereof. This nipple threadably engages with asuitable seat on the discharge head. Hence the discharge head of theinvention can be effectively employed with a wide variety of shapes andsizes of tanks 12 and for various rates of discharge merely by couplingthe proper tube 13 thereto.

The discharge head 10 comprises six basic elements, namely, the housing16, the valve and stem assembly 17, the valve operating handle 18, afixed handle 19, a pressure gauge 20 and the locking device 21. Thevalve housing 16 has an enlarged lower portion 22 terminating in adownwardly extending tubular part 23 having external threads 24 andinternal threads 25. The internal threads 25 are arranged to receive theadapter 15 carrying the discharge tube 13. It is desirable to maintain areasonably good seal between the adapter 15 and the lower end 23 of thehousing 16. Normally the seal provided by interlocking threads isadequate, though a gasket may be employed if desired. The externalthreads 24 on the portion 22 are for engagement with a correspondingthreaded opening in a suitable fitting secured to the top of the tank orbottle 12. The valve housing 16 is seated 1n sealed relation withrespect to that fitting by a pair of 9 rings 26 and 27 carried insuitable recesses 26 and 27 in the housing 16. The details of thisrelationship will be set forth in a companion application by the instantinventors.

The outlet passage 28 of the housing 16, defined in part by the threads25 on the lower end thereof, extends upwardly into a tapered section 29which latter serves o receive and cooperate with the improved valve 30forming part of the valve and stem assembly 17. The tapered wall 29actually forms the valve seat and will be discussed in greater detail asthe description proceeds.

The upper end of the tapered section or seat 29' terminates in acylindrical section 31 which in turn communicates with a transverseopening 32 having a threaded portion or mouth 33 for attachment of asuitable nozzle generally denoted by the numeral 34 (FIGS. 2 and 3). Thenozzle 34 may be in any desired form or it may be coupled to the mouthor exit 33 of the extinguisher by means of a flexible hose. In the caseof powder type extinguishers wherein the powder is loaded into thecylinder 12 and then the discharge head 10 is secured to the cylindersas previously described, the mouth 33 is used for the attachment of agas injection adapter 35' illustrated in cross section in FIG. 1.

The valve operating assembly 17 includes, in addition to the valve head30, a valve stem 36 extending upwardly through an opening 37 in thevalve housing and into an enlarged chamber 38 in the upper end of thebody 16. The chamber 38 includes a pair of gaskets 39 and 40 firmlyseated in the bottom thereof and snugly receiving the valve stem 36. Theupper end of the valve stem 33 is provided with a cylindrical valveoperating member 41 threadably secured thereto by means of threads 42and extending upwardly beyond the top of the housing 16. A spring 43 isdisposed between a flange 44 on the valve operating member 41 and bearsdownwardly against the gaskets 39 and it to secure them in place andseal the opening 37. The spring also acts to move the valve operatingmechanism 41 upwardly to urge the periphery of the valve head 30 intocontact with the tapered wall of the valve seat 29 to close the valve.

The valve operating member 41 is guided within the chamber 38 by meansof an annular cap 45 threaded at 46 to the upper end of the housing 16.The cap is sealed to the end of the housing 16 by means of a gasket 47and is slidably sealed to the periphery of the valve operating member 41by means of an ring 48 disposed in a recess formed in the wall of theopening 45 in the cap. This 0 ring serves as a guide for the member 41and to seal against weather.

The valve 39 in the illustrated embodiment of the invention is in theform of two cones with their large ends opposed and with resilientWasher or ring 30 disposed about a seat at that position. Thisstructure, to be described in detail hereinafter, enables the resilientring 31'? to effect an initial seal against the tapered opening 29 onupward motion of the valve stem. This motion is, however, limited bycontact of the periphery of the upper cone with the tapered side wall29. As this contact, or engagement, takes pace the ring 30' is deformednot only by the movement of the valve, but also by the pressure of thegas in tank 12 to insure a positive and dependable seal.

The operation of the valve 30 is accomplished by the handles 18 and 19,the latter being a so-called fixed handle pivotally attached at 49 to alug 50 formed integrally with the valve housing 16. The handle 18 is inthe shape of an L with the short leg 51 thereof pivoted at 52 to 2. lug53 formed as an integral part of the housing 16 and on the side thereofopposite to the lug 59. The longer leg 54 of the handle 18 has a roundedsurface 54 which engages the rounded operating surface 4-1 of the valveoperating mechanism 41. Hence, when the handle 13 is depressed, thevalve assembly 17 and the valve head 30 are moved downwardly against theaction of the spring 43 and against the effect of the pressure in thebottle 12 to open the valve and permit the fire extinguisher medium topass upwardly and outwardly through the exit 33.

In order to prevent the valve from being accidentally operated bydepression of the handle 54, a safety locking device 21 is provided.This is in the form of a clip 64 of spring steel, prosphor bronze orother resilient material and having a circular handle 70 attachedthereto. The clip 64 is in the shape of a U with the legs 65 and 66having portions thereof arcuately formed as indicated at 66' and 65 toengage the cylindrical body part of the valve operating member 41. Theouter ends 67 and 63 of the clip are bent outwardly to facilitate theinsertion of the clip about the valve operating member 41 and betweenthe underside of the handle 18 and the top side of the cap 45 on thebody 16. When this clip is in place on the member 41 it bridges thespace between the handle 16 and the cap 45 and prevents accidentaldepression 01 the handle 18 and consequent operation of the valve 30.

As pointed out above, the valve 30 is moved into the closed position bythe conjoint action of the spring 43 and the pressure within the tank12. If desired, added closing force may be applied by manual operationof the handle 18 in an upward direction though that is rarely necessary.Alternatively, of course, the spring 43 can be made strong enough to dothe complete closing job. This would, of course, allow for reversing theaction of the valve to close it by downward action against a seatreversely tapered or formed with respect to the taper of the seat 29.

The valve 30, in the illustrated embodiment of the invention, as bestseen in FIGS. 58, comprises three basic elements, namely an upper cone80, a lower cone 81 and a flexible ring 30 of rubber, plastic or othersuit able material. The upper cone is centrally bored at 82 for slidablereception on the reduced end 83 of the shaft 36. Thus the small end 84of the cone abuts against the shoulder 85 formed where the reduced endof the shaft commences.

The large end or base of the cone 89 is recessed around its periphery toform one side of a seat for the gasket 30', which seat is bordered by anannular surface 86 inclined upwardly and inwardly with respect to aplane at right angles to the axis of the cone. That surface terminatesat its inner end at a cylindrical shoulder 87 coaxial with the cone.

The top plane surface, or base 88 of the lower cone 81 has a borderingannulus 38 opposing the surface 86 and forming the other side of theseat for the gasket 30. The annulus 88 is inclined downwardly withrespect to the plane of the base 88. Thus, as the cones 80 and 81 areassembled and tightened up on the end 83 of the shaft 36, the gasket 30"will be forced inward on its seat between the surfaces 86 and 88' andwill be strongly held against any forces tending to dislodge it. Thevolume of the gasket 30' is such that it fills its seat and only acontrolled part 30" of it is allowed to extend outwardly therefrom inthe form of a rounded nose.

The slopes of the cones 8t) and 81 are preferably the same and the cone81 holds the assembly together and in place on the stem 36. This is dueto its threaded bore 91 which threadedly engages the extension 83 of theshaft 36. The small end of the cone 31 is preferably slotted, orotherwise formed as shown at 92 to receive a tool for applying andremoving it. Conveniently also the stem 36 is bored at 93 for thereception of a pin, or other suitable member, so that the stem 36 can beheld while the cone 81 is being applied or removed.

For a showing of the manner in which this valve is related to its seat29 in various positions, reference is made to FIGS. 6, 7 and 8. In FIG.6 the valve is shown in its open position with a passage between theradiused nose 30" of the gasket 30 and the tapered side 29. The pascageis sufficient for the discharge of the fire extinguishing medium at therate desired. Furthermore, the opposed conical surfaces of the parts 80and 81, taken in conjunction with the conical seat 29, direct the flowin a uniform manner, reducing turbulence to a minimum.

On the initial closing step of the valve, as seen in FIG. 7, the nose30" of the gasket wipes against the seat 29 cutting off the flow of theextinguishing medium, whether liquid or powder, cleans off that seat,and then seats against it to form an initial seal. Once such a seal iseffected further sealing is enhanced by the pressure within thecontainer acting below the gasket and deforming it against the seat 29.Thus, a quick cutoff is achieved and a tight closing readily effectedonce the spring and pressure action Work together.

In the iinal closed position, as seen in FIG. 8, the periphery 90 ofannulus 86 has come into contact with the seat 29. This is a metal tometal line contact about a line 94 and it forms as tight a joint as canbe achieved by metal to metal contact. Assurance that this joint iscompletely tight is, of course, achieved by the presence of the extendednose 30" of the gasket 30. This gasket is compressed inwards anddeformed downwardly and makes a positive seal against the seat 29.Pressure acts upon it even in the fully closed position, since the seat29 tapers outwardly in its downward extent, leaving a small spacebetween the periphery 89 of the cone 81 and the seat 29.

Long and effective life of the gasket is assured, however, since it isbacked up by the metal of the cone 80 so that there is practically nospace over which unsupported gasket material has to withstand the effectof the pressure within the container. The gasketing is in a sense ahighly effective packing, but one Which can be removed and reseated asdesired.

The recessing of the upper and lower cones 80 and 81 at 86 and 8-8 toreceive the gasket enables the gasket to effect its sweeping or wipingaction as the valve is closed without danger of its popping out.

The valve structure and action of the invention achieve results whichhave been out of the question with prior constructions. First the valvepositively prevents the possibility of it being held open after apartial discharge, by powder building up and being compacted on thevalve seat. This is due partially to the wiping action of the gasketsurface 30" as the valve closes, but more positively to the metal linecontact between the periphery 90 of the annulus 86 and the surface 29.There is no fiat surface contact on which powder can compact to blockthe closing action. On the contrary, there is a line or knife-likecontact which would cut through any powder or push it aside due to thediverging tapers of the cone 80 and its seat 29. This effective closingaction would persist whether the closing were pressure assisted or weremerely spring induced as where the valve closed downwardly against areversely tapered seat.

Secondly, the valve needs no adjusting to make it seat properly. By thenature and relationships of its parts it eliminates any need foradjusting because it is self adjusting. \All that is needed is to makesure that the valve member is turned all the way in on one end of thevalve stem and that the valve operating member 41 is turned all the wayin on the other end. This establishes the proper relationship betweenthese parts so no adjusting is needed to achieve that relationship.

The valve of the invention is, accordingly, a most effective one formeeting the rigid requirements of fire extinguisher use-positive sealingagainst relatively high pressures for long periods of time without use,quick and effective opening whenit needs to be used, and effective andpositive closing after each use. Nevertheless, the valve is formed forsimple assembly and disassembly should it be desired to replace thegasket 30'.

While only one embodiment of the invention has been shown and described,it is understood that changes, modifications and alterations that mightsuggest themselves to one skilled in the art may be made withoutdeparting from the true scope and spirit thereof.

Having described our invention, what we claim as new and desire tosecure by Letters Patent is:

1. A valve for a dry powder fire extinguisher comprising -a pair'offrusto conical members positioned in base to base relationship andhaving axially spaced peripheral edges of substantially the samediameter, a valve stem slidably and axially extending through the upperof said members and threadedly received in the lower of said members andstep means toposition the upper of said members on said stem to maintainsaid members in base to base engaged relationship, and an annularresilient gasketing member secured between said opposed bases and havinga portion extending out to a small extent past said opposed peripheraledges.

2. A valve and seat assembly for a dry powder fire extinguishercomprising a tapered conical valve seat converging away from thepressure end thereof, a valve cooperating with said seat and comprisinga frusto conical member tapered in the same direction as the taper ofsaid seat but at a greater slope with respect to the axis of said seatthan the slope of said seat, the base of said member having a greaterdiameter than that of the smaller end of said seat whereby a metal tometal line contact can be effected between said base and said seat tolimit the closing action of said valve, an annular resilient elementseated around the periphery of said frusto conical member on thepreessure side of said base and formed for engagement with said seat inaddition to said metal to metal line contact when said valve is closed,means for holding said annular element in tight contact with said base,and said annular element normally extending radially outwardly withrespect to the periphery of said base and forming pressure responsivemeans to hold said periphery against said seat and to form a positiveseal between said frusto conical member and said seat, said holdingmeans being formed as an additional frusto conical member having a baseof substantially the same peripheral diameter as that of said firstfrusto conical member, said base of said additional frusto conicalmember overlying substantially all of said resilient element except thevalve seat engaging portion thereof.

3. In valve construction for dry powder fire extinguishers, a housing,including a valve and seat assembly, said assembly comprising a taperedconical valve seat converging away from the pressure end thereof, avalve cooperating with said seat and comprising a frusto conical membertapered in the same direction as the taper of said seat but at a greaterslope with respect to the axis of said seat than the slope of said seat,the base of said member having a greater diameter than that of thesmaller end of said seat whereby a metal to metal line contact can beeffected between said base and said seat to limit the closing action ofsaid valve, an annular resilient element seated around the periphery ofsaid frusto conical member on the pressure side of said base and formedfor engagement with said seat in addition to said metal to metal linecontact when said valve is closed, means for holding said annularelement in tight contact with said base, and said annular elementnormally extending radially outwardly with respect to the periphery ofsaid base and forming pressure responsive means to hold said peripheryagainst said seat and to form a positive seal between said frustoconical member and said seat, an exhaust chamber formed in said housingand being in open communication with the smaller end of said conicalvalve seat, a valve stem being concentric with respect to said valve,extending through said chamber and engaging said valve concentrically atthe end of said frusto conical member opposite the base thereof andbeing secured to said valve for actuating the same.

(References on following page) References Cited in the file Of thispatent UNITED STATES PATENTS Forestier June 18, 1889 Miller July 19,1898 Boyce Jan. 11, 1921 Hampton July 6, 1929 Wile Aug. 18, 1936 HoofMar. 18, 1947 Allin Apr. 13, 1954 Bashark Feb. 1, 1955 55 Rand Mar. 22,1955 Nurkiewicz Mar. 12, 1957 Hollander Apr. 15, 1958 Mascusi Aug. 5,1958 Novotny Sept. 15, 1959 FOREIGN PATENTS Australia of 1954 GreatBritain Feb. 2, 1955

